Improvement in mill-picks



NITE

' .WENT FFICE.

IMPROVEMENT lIN MILLPICKS.

Specication forming part of Letters Patent No. 52,6, dated February 20, 1866.

To all whom it may concern:

Be it known that I, GHARLEs CRossLEY, of Philadelphia, Pennsylvania, have invented an Improvement in Millstone-Picks; and I do hereby declare the following to be a full, clear, land exact description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

My invention consists of certain devices, fully described hereinafter, whereby the steel bit of a millstone-pick may be firmly secured in its position, readily detached when required, and adjusted as it is worn away.

In order to enable others skilled in the art to make and use my invention I will now proceed to describe its construction and operation.

On reference to the accompanying drawings, whichi'orm a part of this speciiication, Figure l is a longitudinal section of my improved millstone-pick 5 Fig. 2, a section on the line 1 2, Fig. l; Fig. 3, a detached sectional view, and Fig. 4 an exterior view, of part of the pick.

A is a metal plate, the lower face of which is so cut away as to form two ribs or tlanges, a c', the Lipper edge, w, ot' each of the latter being inclined, as shown in Fig. 3.

To the upper end of the handle X of the pick is secured a wedge-shaped plate, C, the inclined edges yg/ of which, when a pick is ready for use, bear against the inclined edges x as of the Bauges c a.

B is a bit, which consists of a steel plate sharpened at each end and having on the upper side a lug, c, which is adapted to recesses c e', in the lower face of the plate A.

The bit B is tirst adjusted to the position shown in Fig. l, the lug c projecting into the recess e. rlhe end of the wedge-plate C is then introduced between the bit B and the ianges a c', and the plate is pushed forward When the pick is used the main force of the blow is received by the lug o, while at each stroke the wedge-plate O is driven forward, the bit being thus wedged firmly in its position, so that it cannot become loosened and rattle, as in picks of the ordinary construction.

When that portion of the bit projecting beyond the plate A is nearly worn away the wedge-plate C is withdrawn, and the bit is moved forward until the lug c is introduced into the recess, e, after which the wedge-plate is brought to its first position, when the pick is again ready for use.

When, after the second adjustment of the bit, the projecting portion 0f the same has been entirely worn away, the bit is removed and reversed, and the opposite end is used in a similar manner.

The wedge-plate C may be withdrawn to detach the bit by grasping the handleX and striking the end x of the plate A against any hard substance.

A pick of this description is simple in construction, cheap, and cannot get out of order. The bit may be used un til almost entirely Worn away, is retained firmly in its position, and yet may be instantly detached when it is necessary to sharpen or adjust the same.

I claim as myinvention and desire to secure by Letters Patent- The combination of the recessed plate A with its flanges c a', the wedge-plateC, secured to a handle, X, and the bit B, with its lugs c, the whole being constructed substantially as and for the purpose described.

In testimony whereof I have signed my name to this specification in the presence-of two subscribing witnesses.

CHARLES GROSSLEY.

Witnesses:

CHARLEs E. FOSTER, J oHN WHITE. 

